In order to keep pace with Moore’s law, it is necessary to make these transistors smaller, meaning the insulating layer must be made thinner. Thinner layers of SiO2 allow current to
leak through the insulating layer, and the limit of SiO2 layer miniaturization is being approached (Brand). It is therefore necessary to find a replacement dielectric material if the pace of
development suggested by Moore’s law is to continue. The replacement material must have a higher dielectric constant or provide reduced current leakage. Strontium titanate (SrTiO3) has a larger
dielectric constant and a thicker layer can be used to mimic the performance of the SiO2 insulating layer, thus allowing for further size reduction. The goal of this project was to determine the
coverage of SrTiO3 on a silicon substrate. The SrTiO3 was grown on silicon to follow the current use of silicon in transistors. It is necessary to investigate the coverage because reduced coverage
will not allow the SrTiO3 layer to block leakage currents in a transistor. Plan view and cross section view samples of the material were prepared and analyzed using scanning transmission electron
microscopy. Multislice simulations were also used to determine the visibility of strontium atoms on silicon lattice.
Cornell Center for Materials Research
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Acknowledgements: This work was supported by the Cornell Center for Materials Research and the National Science Foundation